Dics of Tron by Midway came out after Deadly Discs and is a very different game.

Aha! Thanks. I think there was a TRON arcade, with three mini-games. Although I do not know if one of them was Deadly Discs. Like I said, I probably confused those.

There's also Motorcross, by Rick Koening.

FUN FACT:Motorcross is pretty much the precursor to Racing Destruction Set on the C=64 (one of my most favourite games on that platform). The math routines for the physics simulations on the former were reused on the latter. Also, on Stadium Mud Buggies, another original Intellivision title, although that one was also ported by INTV Corp. to the Nintendo NES.

I can't recommend Motocross. Stadium Mud Buggies, by the same programmer, is far more playable. My favourite Intellivision racing game is still Auto Racing; be sure to only play one player mode.

The first Tron arcade game came out at about the same time as Deadly Discs and Mazeatron. The arcade game has four mini-games, none of them resemble the Intellivision games; light cycles is similar to Snafu.

I can't recommend Motocross. Stadium Mud Buggies, by the same programmer, is far more playable. My favourite Intellivision racing game is still Auto Racing; be sure to only play one player mode.

My favourite is also Auto Racing.

I just mentioned Motorcross because it is an original, as requested at the top of this thread. I find Motorcross and Stadium Mud Buggies to be just as playable, by which I mean, equally cumbersome to control. I must prefer Racing Destruction Set for its fluidity and larger screen real-estate in which to manœuvre. Then again, that's not an Intellivision game, but it does feel like the culmination of its previous incarnations on the Intellivision.

Auto Racing can be consider an original, but does it fall under the "sports" category the original poster was trying to avoid? It doesn't for me, but his mileage may vary.

Also, a Biplanes-esque game also came out on the Bally system (Red Baron) at least a year before Triple Action came out, although it lacks Biplanes' physics. Both were probably derived from some late '70s arcade title, but I'm too lazy/busy to research right now. Tracing further back, there was also Spitfire on the Fairchild.

'Kay, done being a dick now.

Beamrider, if not already said
Another great game by Mr. Rolfe, which came out first for Intellivision, IIRC

Once all the other versions come out, though, "first" no longer means "exclusive."

My memory is growing more faulty by the day, so it's unclear if there were antecedents that would have formed the basis for these games. Now -- most would not consider these the gems of the platform (personal opinions aside -- i enjoy the first two games on this list) -- but perhaps they are -- and deservedly remain -- unique to Intellivision.

EDIT: I also lost track of the exclusivity aspect -- so Sewer Sam and maybe Blockade Runner would be off this list, as well as Kool-Aid Man.... But the Atari version was so different, they're really alike in name only.

Also, a Biplanes-esque game also came out on the Bally system (Red Baron) at least a year before Triple Action came out, although it lacks Biplanes' physics. Both were probably derived from some late '70s arcade title, but I'm too lazy/busy to research right now. Tracing further back, there was also Spitfire on the Fairchild.

'Kay, done being a dick now.

Once all the other versions come out, though, "first" no longer means "exclusive."

Those Atari conversions don't play like the Intellivision originals, partly because of the Intellivision controller. Is there a technical reason they changed the screen orientation for Atari 8-bit Dreadnaught Factor. You can't see as much of the dreadnaughts; otherwise it looks faithfull.

The reason I bought Triple Action back when it came out was because I liked playing the old arcade biplanes so much. But Intellivision Biplanes is so much better and significantly improved to make it unique. Technically, the Atari Combat cartridge has a biplanes variation.

It might just be me but I find the Imagic games to be overrated. I do appreciate their uniqueness.

No question Vectron is exclusive and unique, but I can't recommend it. [too frustrating]

If we're talking 1 player sports games... here is the list that hasn't been mentioned. All Intv originals. All great titles and fun to play.

Getting off topic here but Chip Shot coming out in 1987 was preceded by famicom/nes golf with a similar mechanic, not to mention other more advanced golf games like Leaderboard. PGA Golf (1980) does have most of that mechanic. I know I've said it before but I much prefer the original Intellivision Football, Hockey, Basketball, and Soccer to the super pro versions. The updated versions have flaws making them unplayable to me. Not sure how unique Spiker was for 1989 as a volleyball game.